15.2. The from clause

The simplest possible Hibernate query is of the form:
from eg.Cat
This returns all instances of the class eg.Cat. You do not usually need to qualify the class name, since auto-import is the default. For example:
from Cat
In order to refer to the Cat in other parts of the query, you will need to assign an alias. For example:
from Cat as cat
This query assigns the alias cat to Cat instances, so you can use that alias later in the query. The as keyword is optional. You could also write:
from Cat cat
Multiple classes can appear, resulting in a cartesian product or "cross" join.
from Formula, Parameter
from Formula as form, Parameter as param
It is good practice to name query aliases using an initial lowercase as this is consistent with Java naming standards for local variables (e.g. domesticCat).